Abstract : Irradiation to 3x10 to the 21st power ev/g of solutions of stannic chloride (SnCl4) in toluene at 195 K by 1-Mev electrons gave o- and m- and/or p-chlorotoluene yields (G, molecules/100 ev) which were unaffected by changes in temperature and dose and by the presence of ethylene and nitric oxide, but rose with SnCl4 concentration to approach a limiting total value near 0.2. When ethylene was present, G(total C9H12) was near 0.01. When CCl4 was substituted for SnCl4, a different product pattern was found. Squalene was irradiated with Co-60 gamma rays at room temperature and with 1-Mev electrons at 243 K. The main radiation -induced effects, with their G-values at room temperature, are loss of unsaturation (4.6), crosslinking (1.35), trans-cis isomerization (0.83), and hydrogen evolution (0.58). Most of the loss of unsaturation is attributed to cyclization; it occurs only in the crosslinked fraction. Increased yields (on the basis of energy absorbed in the solute) were observed for the cis-trans isomerization of squalene and cis- and trans-polyisoprene when these were irradiated in benzene solution. The chlorination of toluene and the cyclization of cross-linked squalene are believed to have ionic intermediates. (Author)